The present invention relates particularly to a developing device for carrying out a wet processing utilizing a silver halide photosensitive material or the like, or to an image recording device or the like which includes such a developing device.
Various kinds of automatic developing machines utilizing a silver halide photosensitive material and copying machines which include such an automatic developing machine and an exposure device have so far been developed.
Such an automatic developing machine is equipped with a liquid tank portion consisting of a developing tank, a bleaching and fixing tank, and a water washing tank; and a drying portion for carrying out drying after wet processing. Further, the turning on and off of heating means, such as a heater provided for each of the liquid tank portion and the drying portion, is controlled in order to maintain the respective portions at desired temperatures.
In the conventional automatic developing machine, however, control of each of the heaters is executed completely independent of each other, with a possibility of simultaneous application of the power supplies for the respective heaters, so that the capacity of the machine is determined by the sum of the power supplies to be applied.
However, a recently developed automatic developing machine or a copying machine for a minilab requires that it be used under a rated household power supply of 100 V and 15A, which makes it necessary to reduce the power capacity of the machine.
Under these circumstances, there is disclosed in Japanese Patent Laid Open, Gazette No. 61-70557, a temperature control system for an automatic developing machine which is intended for reducing the power capacity.
In the above-mentioned system, a priority order is set in advance for a plurality of heaters provided in each of the liquid tank portion and the drying portion. At the same time, a heater activation period for a predetermined time, e.g., several seconds, is also prescribed. With such an arrangement, single cycles for the heating time of the heaters are allocated, in accordance with the priority order, to a combination of heater activation times which will not cumulate simultaneous activation of multiple heaters to exceed the rating limits.
However, in this system, heaters with a lower priority order will not be actuated within one cycle of the heater activation period even when they are required to be heated, and hence, the tanks or the drying portion with a lower priority order is forced to be sacrificed during a temperature stabilized period, so that maintenance of the temperature in an efficient manner fails to be accomplished.